Illustration Shows E60/E61/E63/E64:

WARNING: This page is about a different car, the 2005 BMW 645Ci and 2004 BMW 645Ci. However, it is still accessible from the selected car via links, so may be relevant.

Perform filling operation slowly.

Pour coolant into expansion tank up to MAX mark.

Start engine and run at idle speed for approx. one minute (cap open). Then adjust coolant level to MAX.

Close cap and run engine up to operating temperature until main thermostat opens. Check cooling circuit and drain plug for leaks.

Fig 1: Locating Expansion Tank Coolant Filling Mark (E 60/E 61/E 63/E 64)

Courtesy of BMW OF NORTH AMERICA, INC.

IMPORTANT: The engine must be cooled down before the coolant level is checked. Coolant temperature must not exceed 30 °C. If ambient temperature is above 30°C, allow engine to cool down to ambient temperature at least.

Check coolant level and adjust to MAX.

NOTE: Do not fill coolant expansion tank over MAX level as overfilling will cause the coolant to overflow.